This section is from the book "Harper's Guide To Wild Flowers", by Caroline A. Creevey. Also available from Amazon: Harper's Guide To Wild Flowers.
Color, purplish blue. Leaves, fleshy, all clustered at the root, submerged, hollow, obtuse, with a partition through the middle. Roots, white, fibrous. Flowers, in a loose, terminal raceme, few, with pedicels. Scape, thickish, 6 to 18 inches high. July to September.
An aquatic, in ponds, near the borders, often wholly immersed. New Jersey and Pennsylvania northward.
L. Canbyi. - Color, deep blue. Flowers, on pedicels, in loose racemes, with linear bracts. Leaves, linear, very narrow above. Stem, erect, branched, 2 to 3 feet high. Corolla, bearded in the tube. Calyx, with long, thread-like teeth.
 
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